Abstract
Increased temperature anomaly during the twenty-first century coincides with the proliferation of transgenic crops containing the bacterium Bacillus thuringiensis (Berliner) (Bt) to express insecticidal Cry proteins. Increasing temperatures profoundly affect insect life histories and agricultural pest management. However, the implications of climate change on Bt crop–pest interactions and insect resistance to Bt crops remains unexamined. We analysed the relationship of temperature anomaly and Bt adoption with field-evolved resistance to Cry1Ab Bt sweet corn in a major pest, Helicoverpa zea (Boddie). Increased Bt adoption during 1996–2016 suppressed H. zea populations, but increased temperature anomaly buffers population reduction. Temperature anomaly and its interaction with elevated selection pressure from high Bt acreage probably accelerated the Bt-resistance development. Helicoverpa zea damage to corn ears, kernel area consumed, mean instars and proportion of late instars in Bt varieties increased with Bt adoption and temperature anomaly, through additive or interactive effects. Risk of Bt-resistant H. zea spreading is high given extensive Bt adoption, and the expected increase in overwintering and migration. Our study highlights the challenges posed by climate change for Bt biotechnology-based agricultural pest management, and the need to incorporate evolutionary processes affected by climate change into Bt-resistance management programmes.
Highlights
Climatic change, as indicated by the highest global average temperatures on record, impacts agricultural productivity2017 The Authors
We address the role of increasing temperature anomaly and its interaction with agricultural biotechnology (Bt crops) to understand some of the indirect impacts of climate change: crop–pest interaction, efficacy of Bt corn for insect pest management and Bt resistance in insects
The interactive influences of temperature anomaly and log Bt acreage significantly influenced the abundance of H. zea over the past two decades (F1,77 = 35.6, p < 0.001, pseudo-R2 = 0.53; see table 1 for coefficients)
Summary
As indicated by the highest global average temperatures on record, impacts agricultural productivity2017 The Authors. As indicated by the highest global average temperatures on record, impacts agricultural productivity. With the increasing average temperatures, agricultural yield losses and management costs are expected to rise due to the changes in geographical range and infestation intensity of crop pests [2,3]. Crop–pest interactions and biological control effects are complex and poorly understood in the context of climate change. Direct climate impacts on pests (e.g. life-history traits) are better understood than the indirect effects (such as crop–pest interactions and biological control) resulting in a gap between the science of predicting changes and management options [4,5,6]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
